Mine doesn’t have a tablet and only gets to use DP’s for school stuff (he’s 4) but is probably having about 3 hours of TV per day (broken down into an hour first thing, lunchtime and before dinner). He often plays while watching. We also have a 4 month old.
I would prefer it to be less but he does school work, plays imaginatively with toys, draws, likes board games and also does things like baking, as well as playing in the garden and going for walks. So I feel this is OK.
I find he’s most difficult, in descending order, after tablet time, TV in short episodes (as he can now choose his own episode and jump around), then TV where it runs for longer, eg Julia Donaldson films. Basically, the shorter the attention span required, the worse the effect! YouTube is banned for this reason.
I don’t personally think all screen time is created equally, but boundaries and limits are important. At this age, I think the question is what they’re not doing when they’re having screen time, if that makes sense - it’s important they have time doing rather than just reacting, if you see what I mean?